Set the update locations to default in CacheLocation's constructor

Otherwise the applypatch executable will fail to back up the source
file to /cache when patching the recovery image.

Bug: 74198354
Test: run applypatch from boot to recovery
(cherry picked from commit b4e3a370)

Change-Id: I37b7fd88d66ab49ef953d4b7dca22577bd1472e1